1) Field of the Invention
This invention relates to a battery powered assist apparatus for a manually operated vehicle such as a bicycle, and more particularly to a new and novel construction of a powered assist apparatus for that bicycle.
2) Description of the Prior Art
The subject matter of this invention has been found to be particularly useful in conjunction with bicycles. However, it is within the scope of this invention that it could be used in conjunction with other manually operated vehicles such as tricycles, scooters and the like.
Electric powered bicycles are well known. Electric powered bicycles generally incorporate an electric motor powered by a rechargeable battery. The electric motor is connected to a drive wheel which frictionally engages with a wheel of the bicycle. Operation of the drive wheel supplies power which supplements the manual movement of the bicycle. These prior art types of power assist devices for bicycles have offered solutions toward significant powering of a bicycle with the motor by permitting usage of the bicycle in a normal manner. These prior art solutions have, however, been mechanically and or cosmetically complex. The past designs have been inclined toward adding mechanical hardware rather than toward the utilization of existing bicycle hardware Extra gears, gear boxes, chains and sprockets are often featured conspicuously on such designs. Also, motor accessories such as throttles, belts and shields are also commonly featured. Additionally, the complexity of the prior art devices has inherently substantially increased the cost of such devices.
Air pollution has become an increasing undesirable problem due, in part, to the increase in use of automobiles and motorcycles. Air pollution is particularly acute in cities. It has been known that one way to improve air quality is to decrease the usage of automobiles and motorcycles. People use automobiles and motorcycles not only for longer trips but for short term travel close to home such as "running to the store." One way to decrease air pollution is to use a bicycle for making these short trips in close proximity to one's home. However, frequently these short trips require that the operator of the bicycle pedal the bicycle up one or more hills. This generally deters most people from using a bicycle when making such trips. However, if a power assist device was incorporated in conjunction with the bicycle, then possibly a user may be more apt to use a bicycle when making such trips since the overall effort to be expended by the operator would be decreased.
In the past, designing a practical, economical electric propulsion system for a bicycle has proven to be a formidable task. This task is evidenced by the absence of electric powered bicycles in commercial production at this time. An electrically operated bicycle, which effectively competes against other forms of transportation, remains lacking.
The prior art direct drive power assist for a bicycle has invariably required a right angle gearing arrangement utilizing bevel gears. Such gearing arrangements are complex as well as noisy. The fact that the axis of the motor is located at a right angle to the wheel axis of the bicycle inherently produces a complex and more expensive driving arrangement for the bicycle. Also, the prior art power assist apparatuses have made it difficult to remove and replace the wheel of the bicycle for tire repair and/or replacement.